Temperatures can fall by up to 4C downwind of farms
Tory MPs write to PM demanding dramatic subsidy cuts
By Chris Slack
Last updated at 6:35 PM on 5th February 2012
They have long been championed as a way to combat global warming by creating clean energy.
But wind farms can actually alter the climate according to a new study by a group of American scientists.
The team from the University of Illinois found that daytime temperatures around wind farms can fall by as much as 4C, while at night temperatures can increase.
The study found that currently the effect is restricted to areas near to the turbines, but the increase in larger farms could create weather changes on a regional scale.
The study was led by Somnath Roy, assistant professor of atmospheric sciences at the university, with the San Gorgonio wind farm in California the focal point of his research.
He found that the day ground temperature behind turbines was up to 4C lower than in front.
He suggested that the turbines’ blades scoop warm from the ground and push the cooler air downwards. This is then reversed at night.
Roy, whose findings were published in the Sunday Times, added that he believes the turbines causing turbulence and reducing winds speed are the cause.
He also added that the churning of air from low to high can create vortices that could extend the phenomenon for large distances downwind.
Roy’s research is supported by a study undertaken by the Iowa State University, who looked at how a 100-turbine farm would affect conditions on farmland.
They found that temperatures on the ground were warmer at night, which in turn allowed plants to breathe more.
While scientists in the United States have conducted research into the effects of wind farms on climate, such research in the UK is at an early stage.
Currently no measurements have been made on changes to weather around British farms despite plans to increase turbines by tenfold.
The UK currently has 3,500 wind turbines, with a further 800 under construction.
The Government aim to have 10,000 onshore and 4,300 offshore by 2020, but the rapid growth has led to 101 Tory MPs writing to David Cameron about the proposal.
The members are calling for a dramatic cut in subsidies to onshore wind farms and more influence for local people to stop them being built.
The move is seen as a major revolt against government policy and sees the politicians join forces with other parties to express serious concerns over the level of taxpayers’ money going to the sector.
The letter was organised by backbencher Chris Heaton-Harris and has senior signatories including David Davis and Nicholas Soames.
In the letter, which was seen by the Sunday Telegraph, they wrote: ‘In these financially straitened times, we think it is unwise to make consumers pay, through taxpayer subsidy, for inefficient and intermittent energy production that typifies onshore wind turbines.’
They also expressed concerns that the proposed National Planning Policy Framework ‘diminishes the chances of local people defeating onshore wind farm proposals through the planning system’.
State help for one of the most controversial sources of renewable energy is being cut but only slowly, under plans set out by ministers last year.
Speaking about the letter a Downing Street spokesman said: ‘We need a low carbon infrastructure and onshore wind is a cost effective and valuable part of the UK’s diverse energy mix.
‘The Government has commissioned a review of subsidy levels and we are already proposing a cut for onshore wind subsidies to take into account the fact that costs are coming down.
‘We are committed to giving local communities the power to shape the spaces in which they live and are getting rid of regional targets introduced by the last government.’